Cross‐sectional study on university students' mental health during the COVID‐19 pandemic: Exploring the influence of adverse and positive childhood experiences

Abstract Aim This study examined the psychological impact of the COVID‐19 pandemic on university students, focusing on how adverse childhood experiences (ACEs) and positive childhood experiences (PCEs) influence mental health. Methods A web‐based survey was administered to 3000 university students from October 26 to 31, 2022, following the peak of the COVID‐19 pandemic. Mental health assessments included the Japanese version of the Kessler Psychological Distress 6‐Item Scale (K6) for depressive/anxiety symptoms, the Impact of Event Scale‐Revised (IES‐R‐J) for distress, fear of COVID‐19, and a three‐item loneliness scale. Results Of the respondents, 46.9% reported depressive/anxiety symptoms, 55.4% reported distress, and 37.3% reported fear of COVID‐19. Factors such as current psychiatric treatment history and reduced income (either parental or personal) were predictive of worsening depressive/anxiety symptoms, distress, and loneliness. ACEs were found to exacerbate depressive/anxiety symptoms and distress, while PCEs mitigated these symptoms, and vice versa. Conclusion This study underscores the importance of considering both ACEs and PCEs in supporting the mental health of university students. PCEs were found to independently prevent mental health deterioration, including depressive/anxiety symptoms and distress, which may include post‐traumatic stress disorder symptoms, even in the presence of ACEs. Recognizing and fostering PCEs emerged as an effective strategy for mitigating mental health issues.


INTRODUCTION
Coronavirus disease 2019 (COVID- 19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2).Initially detected in Wuhan, China, in December 2019, it has since led to numerous infections and fatalities.In Japan, preventive measures against the COVID-19 pandemic have been enforced through the declaration of a state of emergency and prioritized actions to curb its spread.Mandates such as mask-wearing, avoiding crowded spaces, and maintaining social distancing have been advocated to prevent transmission.This global health crisis has triggered various psychological responses, including traumatic stress symptoms, depression, anxiety, confusion, anger, insomnia, and suicidal ideation, with students being particularly susceptible to mental health challenges. 1,2nce the onset of the COVID-19 pandemic, Japan has witnessed a rise in suicides, particularly among women and young individuals. 3is trend suggests a potential exacerbation of mental health issues due to the pandemic.Students, in particular, have faced unique challenges, including isolation resulting from university closures and the prioritization of online classes.Noda et al. 4 conducted a survey in May 2020, during the initial state of emergency (April 7 to May 25,   2020), and 1 month thereafter, revealing that at least 50% of respondents exhibited mild or greater depressive/anxiety symptoms according to the Japanese version of the Kessler Psychological Distress 6-Item Scale (K6). 5ere is ongoing debate regarding whether the COVID-19 pandemic qualifies as a traumatic stressor leading to post-traumatic stress disorder (PTSD), as per the Diagnostic and Statistical Manual of Mental Illnesses (DSM-5) 6 guidelines, which indicate that a lifethreatening or debilitating medical illness may not necessarily be considered a traumatic event. 7However, a substantial body of research supports the perspective that COVID-19 can indeed be construed as a traumatic stressor, eliciting PTSD-like reactions and exacerbating other related mental health issues. 8,9We adopted this perspective to investigate PTSD symptoms among students.This study used the Japanese version of the Impact of Event Scale-Revised (IES-R-J) 10 to assess distress that may include PTSD symptoms.
In a study examining adverse childhood experiences (ACEs) in the United States during the 1990s, events such as familial abuse and mental illness experienced by individuals up to age 18 years were deemed traumatic, correlating with chronic diseases, mental health disorders, and substance abuse in adolescence and beyond. 11Among college students, higher ACE levels correlate with increased risk of mental health decline over time. 12ACEs have been shown to impact students' mental health during COVID-19 lockdowns. 13Concurrently, during the pandemic, a greater number of ACEs may pose a risk for poorer mental health outcomes.
Conversely, higher levels of positive childhood experiences (PCEs), such as growing up with a supportive caregiver, having close friendships, and maintaining a predictable home routine, predict better mental health in adulthood. 14,15ditionally, research has shown that, during the pandemic, aside from ACEs, the presence of PCEs, including having supportive caregivers or friends, is associated with decreased depressive symptoms, stress, and loneliness. 16However, research on PCEs in Japan remains limited.Given concerns about the deteriorating mental health of students amid the ongoing pandemic, we continuously monitored their mental well-being and explored risk factors for a decline in their mental health.Three years post the COVID-19 outbreak in Japan, we examined the impact of ACEs and PCEs on students' mental health, along with factors such as COVID-19 awareness and sense of coherence (SOC), as investigated by Noda et al. 4 in their study on students' mental health during the pandemic.We hypothesized that PCEs would mitigate the effects of ACEs on depressive/anxiety symptoms, distress, fear of COVID-19, and loneliness.

Participants and procedure
A web survey of students was conducted via MyVoice.comInc., from October 26 to October 31, 2022, following the COVID-19 wave that occurred between July 1, 2022, and September 30, 2022.A total of 3000 students participated in the survey, with 1480 (49.3%) identifying as male, an equal number identifying as female, 20 (0.7%) reporting as neither sex, and 20 (0.7%) omitting a response.Respondents were incentivized with points redeemable for Amazon gift certificates and other items valued at approximately $4.
During this COVID-19 wave, approximately 1.47 million individuals were infected, marking the highest number compared to previous waves.Notably, individuals in their teens and twenties accounted for about 40% of the total infections, with the Omicron BA5 strain being predominant.The age range of respondents spanned from 18 to 25 years, with a mean age (standard deviation [SD]) of 20.6 (1.5) years.Among participants, 163 (5.4%) reported currently receiving psychiatric treatment.

MEASURES
Depressive/anxiety symptoms, distress, loneliness, and SOC The K6, 5 designed to screen for depressive/anxiety symptoms over the preceding 30 days, assessed students' mental health status.
The IES-R-J was employed to evaluate distress. 10This self-report measure, aligned with the DSM-IV definition of PTSD, 17 assessed the difficulty of 22 items experienced after high-stress events (eight intrusion items, eight avoidance, and six hyperarousal).Respondents rated the difficulty of each aspect over the past week on a five-point scale ranging from 0 (not at all) to 4 (extremely), yielding a total score range of 0-88 points.PTSD is suspected with a score of 25 points or more.
To evaluate loneliness, we employed the Japanese version of the three-item loneliness scale (TIL). 18This scale comprised three items: (1) I feel that I lack companionship, (2) I feel left out, and (3) I feel isolated from others.Respondents rated the degree of each loneliness aspect on a four-point Likert scale (1 = never to 4 = often), resulting in a scale score range of 3-12.
We considered SOC as a measure of resilience and utilized the University of Tokyo Health Sociology version of the three-item Sense of Coherence Scale (SOC-3-UTHS) 19 to assess SOC.Developed based on Antonovsky's concept of SOC, 20 this instrument employs a seven-point scale to explore three dimensions: comprehensibility, manageability, and meaningfulness.

Demographic information and changes in COVID-19 awareness
Participants provided demographic details including sex, age, residential area, university affiliation, grade, and current psychiatric treatment (see Table 1).
Additionally, participants were queried about their COVID-19 awareness and economic concerns, responding to statements such as "I feel afraid of COVID-19," "I feel stressed about changes in my daily life due to COVID-19 prevention measures," "I am worried about my future because of COVID-19," and "I feel insecure due to reduced income for myself or my guardian."Using a five-point Likert scale (1 = strongly disagree, 2 = disagree, 3 = undecided, 4 = agree, 5 = strongly agree) participants rated their sentiments over the past 30 days (see Table 2).

ACEs and PCEs
To assess ACEs, participants responded with yes or no to 10 items, inquiring whether they had experienced the following before the age of 18 years: (1) psychological abuse, (2) physical abuse, (3) sexual abuse, (4) psychological neglect, (5) parental divorce or separation, (6) family mental illness or suicide, (7) witnessing domestic violence, (8) family substance abuse, (9) abandonment, and (10) family member imprisonment. 21,22The ACE score represented the count of items receiving a positive response.
T A B L E 1 Demographic characteristics (N = 3000).Due to the sensitive nature of ACE and PCE questions, participants unwilling to answer were not obliged to do so.Results showed that 2713 (90.4%) respondents completed all ACE items (M = 0.56, SD = 1.37, range = 0-10).Among these respondents, 75.7% reported none of the items as applicable, while 0.5% reported all 10 items as applicable.

Characteristic
Regarding the PCEs Scale, 2575 (85.8%) respondents answered all items (M = 7.29, SD = 3.13, range = 0-10).Among these respondents, 7.8% reported none of the items as applicable, while 34.0% reported all 10 items as applicable.Missing values were only found for ACEs and PCEs, ranging from 2.2% to 3.3% of the data for each of the ACEs and from 2.6% to 6.1% of the data for each of the PCEs.In calculating Pearson correlations and performing hierarchical logistic analysis, we included 2462 participants who responded to both ACEs and PCEs.
The ACE and PCE scores and item counts are displayed in Tables 3-5.The Cronbach's α for ACEs and PCEs were 0.801 and 0.897, respectively.

Fear of COVID-19
In suspected PTSD with the pandemic as a stressor.In studies not limited to specific stressors, 42.9% of students in France were symptom-positive according to the IES-R conducted shortly after the peak mortality rate in France in April 2020. 25Similarly, in a study conducted in Spain over an 8-day period starting on March 28, 2020, 50.4% of students were symptom-positive according to the original IES. 26In our study, using the IES-R-J in students without limiting stressors, 55.4% were found to be at risk of severe distress, underscoring the significant impact of the COVID-19 pandemic on students' mental health.
[27][28][29] In our study, we chose to focus on PCEs and their relationship with students' mental health outcomes.Our hierarchical logistic analysis revealed that higher scores on ACEs were associated with increased depressive/anxiety symptoms and distress.Conversely, higher scores on PCEs were associated with decreased depressive/anxiety symptoms and distress, although they were linked to an increased fear of COVID-19.
Experiencing fear during a pandemic can be viewed as a natural response aimed at taking appropriate measures to safeguard against infection.Therefore, PCEs may contribute to fostering a sense of resilience and adaptive crisis awareness during emergencies like the COVID-19 pandemic.
Regarding our hypotheses, we confirmed that PCEs indeed mitigated the effects of ACEs on depressive/anxiety symptoms and distress.However, we found that ACEs did not influence the fear of COVID-19, while PCEs had an exacerbating effect on this fear.
Additionally, neither ACEs nor PCEs showed any effect on loneliness in our study.Interestingly, while our study did not observe a direct effect of ACEs and PCEs on loneliness, previous research has demonstrated that ACEs heightened students' loneliness while PCEs reduced it. 30e relationships among ACEs, PCEs, and loneliness remain relatively unexplored in the literature, indicating a potential avenue for future research.In a systematic review of 58 studies on the impact of PCEs on adult outcomes, Han et al. 29 concluded that PCEs independently predict more favorable outcomes without interacting with or moderating ACEs.Moreover, PCEs are deemed crucial targets for fostering resilience in adults, particularly among those who have experienced significant childhood adversity.Noda et al. 4 reported that a higher SOC, indicative of resilience, correlates with reduced depressive/anxiety symptoms.
However, our current study did not find a significant effect of SOC on depressive/anxiety symptoms when PCEs were included in the model.Interestingly, while Step 1 and Step 2 of our analysis did not reveal a significant relationship between SOC and distress, the inclusion of PCEs led to a reduction in distress.Previous studies 31 have indicated that a strong SOC reduces PTSD symptoms, but our findings are not consistent with these findings.The correlation coefficients between depressive/anxiety symptoms or distress and SOC were low, indicating that as the COVID-19 pandemic progresses, the influence of SOC may diminish, while the impact of ACEs and PCEs, which have a more substantial effect, may become more prominent.
A trend was observed indicating that neither males nor females exhibited depressive/anxiety symptoms of moderate or greater levels, highlighting the importance of focusing on the mental health of individuals with gender dysphoria.

CHILDHOOD EXPERIENCES AND MENTAL HEALTH | 3 of 11 For
PCEs assessment, we employed the benevolent childhood experiences Scale, a 10-item questionnaire developed by Narayan et al.14 and translated into Japanese with Professor Narayan's permission.To enhance comprehension among Japanese participants, we replaced "beliefs" with "places" in the item "Did you have beliefs that gave comfort."Additionally, the original text was interpreted and translated into Japanese for better understanding.Participants responded with yes or no regarding experiences before the age of 18 years, including having a safe caregiver, a good friend, comforting places, enjoying school, a caring teacher, good neighbors, supportive adults, enjoyable activities, positive self-concept, and predictable home routine.The PCEs score represented the count of items receiving a positive response.
Data were analyzed using SPSS Version 29.0.Pearson correlations were employed to examine the associations among the K6, IES-R-J, TIL, SOC-3-UTHS, ACEs, and PCEs.Subsequently, we investigated the significant relationships of ACEs, PCEs, and covariates with: (1) depressive/ anxiety symptoms (K6), (2) distress (IES-R-J), (3) fear of COVID-19, and (4) loneliness (TIL), using hierarchical logistic regression analysis.Dummy variables were established for the dependent variables.The cutoff points for K6 and IES-R-J were set at 9/10 and 24/25, respectively, with dummy variables assigned as 0 or values below the cutoff point and 1 for values above it.While TIL has been tested for reliability and validity, no cutoff point has been established.Therefore, loneliness was defined as a TIL score <7 = 0 and TIL score ≥7 = 1, given that the mean TIL score was 7 (rounded).Fear of COVID-19 was designated as 0 if the respondent answered "I feel afraid of COVID-19" with strongly disagree, disagree, or undecided, and 1 if the respondent answered agree or strongly agree.Covariates included sex, age, current psychiatric treatment, feelings of insecurity due to reduced income, and SOC-3-UTHS score.To examine the effects of ACEs and PCEs on the four dependent variables, hierarchical logistic regression analysis was conducted with five covariates in the first step.ACE scores were added to the five covariates in the second step, and PCE scores were added in the third step.PCE scores were added to the five covariates in the fourth step.
Agree and undecided responses to "Living in insecurity due to reduced income of my guardian or myself" and receiving psychiatric treatment had stronger impacts on depressive/anxiety symptoms.Higher ACEs scores were associated with greater depressive/anxiety symptoms, whereas higher PCEs scores were associated with the opposite trend.DistressIn Step 1, age, current psychiatric treatment, and "Living in insecurity due to reduced income of my guardian or myself" were significantly associated with severe distress.In Step 2, along with these covariates, the ACEs scores also demonstrated significance with an OR of 1.20 (95% CI [1.12-1.29]).When PCEs were added in Step 3, they showed a significant relationship (OR = 0.89, 95% CI [0.87-0.92]).The addition of PCEs with covariates inStep 4 also revealed a significant difference (OR = 0.89, 95% CI [0.86-0.91]).Using Step 3 as a model, the predictors of worsening distress were younger age, receiving psychiatric treatment, and an agree or undecided response to "Living in insecurity due to reduced income of my guardian or myself."Higher ACEs scores were associated with greater distress, whereas higher PCEs scores were associated with decreased distress.

CHILDHOOD EXPERIENCES AND MENTAL HEALTH | 9 of 11 LIMITATIONS
There are several limitations to consider in this survey.First, the online nature of the survey may have introduced bias towards participants with computer skills.Second, the use of screening tools rather than face-to-face diagnosis may have led to an overestimation of the frequency of depressive/anxiety symptoms and distress.Additionally, since the questionnaires were selfadministered, variations in respondents' language abilities and comprehension of the questionnaire could have influenced the results.Furthermore, there may have been a tendency towards central responses due to limited alternative options in the survey questions.Despite these limitations, the findings of this study contribute valuable insights into the mental health of students during the COVID-19 pandemic.CONCLUSION Roughly 47% of students displayed depressive/anxiety symptoms, while approximately 55% exhibited severe distress, which may include PTSD symptoms.Current psychiatric treatment history, experiencing reduced income (either parental or personal), and suspicion of gaming disorder were identified as predictors of exacerbated depressive/anxiety symptoms, distress, and loneliness.Paying attention to these factors is crucial to prevent the deterioration of students' mental health during the COVID-19 pandemic.Further, PCEs emerged as predictors of reduced depressive/ anxiety symptoms and distress.While ACEs are typically associated with mental health risks, such as depressive/anxiety symptoms and distress, this study revealed that PCEs can independently prevent mental health decline, even in the presence of ACEs.PCEs encompass positive childhood experiences at home, in the community, and at school, emphasizing the importance of nurturing environments in fostering good mental health, even amid global crises like the COVID-19 pandemic.Recognizing and promoting PCEs were found to be effective strategies in mitigating mental health challenges.

Table 7
displays the results of the hierarchical binomial logistic analysis.The omnibus tests for each model were significant (p < 0.001).T A B L E 3 Number of ACEs and PCEs applicable.Abbreviations: ACEs, adverse childhood experiences; NA, no answer; PCEs, positive childhood experiences.
OR = 1.07, 95% CI [1.03-1.10]).The addition of PCEs with covariates in Step 4 also revealed a significant difference (OR = 1.07, 95% CI [1.04-1.10]).Using Step 3 as the model, the predictors of exacerbating fear of COVID-19 were female sex, receiving psychiatric treatment, an agree or undecided response to "Living in insecurity due to reduced income of my guardian or myself," higher SOC-3-UTHS score, and higher Step 1, sex, current psychiatric treatment, "Living in insecurity due to reduced income of my guardian or myself," and SOC-3-UTHS were significantly related to fear of COVID-19.When ACEs were added inStep 2, they did not demonstrate a significant relationship with fear of COVID-19 (OR = 0.95, 95% CI [0.88-1.01]).In Step 3, when PCEs were added, PCEs showed a significant relationship with fear of T A B L E 4 Frequencies of ACEs.ACEs Yes (%) No (%) NA (%)T A B L E 5 Frequencies of PCEs.T A B L E 6 Bivariate correlations between variables.T A B L E 7 Hierarchical binomial logistic regression for depressive/anxiety symptoms, distress, fear of COVID-19, and loneliness.